Pacific Gas and Electric Co. executives said Thursday that new criminal charges against the company over the deadly San Bruno pipeline explosion were unwarranted, while reporting lower second-quarter earnings than Wall Street had expected.

A federal grand jury on Tuesday added charges to an existing indictment against PG&E, accusing the company of violating pipeline safety rules and lying to investigators who were probing the September 2010 blast that killed eight people and destroyed 38 homes. The additional charges greatly expanded the potential fines PG&E could face, from $6 million to $1.3 billion.

"Let me just state that based on all the evidence, we still do not believe that any of these criminal charges or fines are warranted," said Tony Earley, chairman and CEO of the utility's parent company, PG&E Corp.

He also repeated that the utility is looking into accusations from San Bruno's mayor that PG&E executives engaged in improper communications with regulators at the California Public Utilities Commission. Recently released e-mails show an exchange in which the chief of staff for the commission's president advised a PG&E executive on ways to avoid releasing public information. The executive replied, "Love you."

"As any regulated utility does, we communicate with the CPUC almost constantly on a wide range of issues," Earley said. "To ascertain whether our communications were appropriate, we will carefully review the documents in question and take appropriate action."

Earley's comments, which echoed earlier statements by the company, came as PG&E Corp. reported a second-quarter profit of $267 million (57 cents per share). During the same period last year, PG&E made $328 million (74 cents).

With one-time items removed, PG&E made $324 million (69 cents). By that measure, Wall Street analysts polled by Thomson Financial Network had expected 74 cents per share, on average.

PG&E reported spending $97 million during the second quarter on pipeline-related costs. The San Francisco company has now spent or has committed to spending $2.7 billion on efforts to upgrade its natural gas pipeline network and operations following the San Bruno blast.